From bedfb7adc7f7e2f344b21584905b2357147ba27e Mon Sep 17 00:00:00 2001 From: Oleg Matcovschi Date: Tue, 15 May 2012 14:35:08 -0700 Subject: [PATCH] ARM: OMAP: dma: Clear status registers on enable/disable irq Use omap_disable_channel_irq() function instead of directly accessing CICR register in various functions. The omap_disable_chanel_irq() function now clears pending interrupts and disables interrupt on channel. Functions omap2_enable_irq_lch()/omap2_disable_irq_lch() clear interrupt status register. Signed-off-by: Oleg Matcovschi Tested-by: Jarkko Nikula [tony@atomide.com: updated comments to clarify CICR access] Signed-off-by: Tony Lindgren --- arch/arm/plat-omap/dma.c | 59 +++++++++++++++++++--------------------- 1 file changed, 28 insertions(+), 31 deletions(-) diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c index cb16ade437cb..7fe626761e53 100644 --- a/arch/arm/plat-omap/dma.c +++ b/arch/arm/plat-omap/dma.c @@ -573,22 +573,25 @@ EXPORT_SYMBOL(omap_set_dma_dest_burst_mode); static inline void omap_enable_channel_irq(int lch) { - u32 status; - /* Clear CSR */ if (cpu_class_is_omap1()) - status = p->dma_read(CSR, lch); - else if (cpu_class_is_omap2()) + p->dma_read(CSR, lch); + else p->dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR, lch); /* Enable some nice interrupts. */ p->dma_write(dma_chan[lch].enabled_irqs, CICR, lch); } -static void omap_disable_channel_irq(int lch) +static inline void omap_disable_channel_irq(int lch) { - if (cpu_class_is_omap2()) - p->dma_write(0, CICR, lch); + /* disable channel interrupts */ + p->dma_write(0, CICR, lch); + /* Clear CSR */ + if (cpu_class_is_omap1()) + p->dma_read(CSR, lch); + else + p->dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR, lch); } void omap_enable_dma_irq(int lch, u16 bits) @@ -632,14 +635,14 @@ static inline void disable_lnk(int lch) l = p->dma_read(CLNK_CTRL, lch); /* Disable interrupts */ + omap_disable_channel_irq(lch); + if (cpu_class_is_omap1()) { - p->dma_write(0, CICR, lch); /* Set the STOP_LNK bit */ l |= 1 << 14; } if (cpu_class_is_omap2()) { - omap_disable_channel_irq(lch); /* Clear the ENABLE_LNK bit */ l &= ~(1 << 15); } @@ -657,6 +660,9 @@ static inline void omap2_enable_irq_lch(int lch) return; spin_lock_irqsave(&dma_chan_lock, flags); + /* clear IRQ STATUS */ + p->dma_write(1 << lch, IRQSTATUS_L0, lch); + /* Enable interrupt */ val = p->dma_read(IRQENABLE_L0, lch); val |= 1 << lch; p->dma_write(val, IRQENABLE_L0, lch); @@ -672,9 +678,12 @@ static inline void omap2_disable_irq_lch(int lch) return; spin_lock_irqsave(&dma_chan_lock, flags); + /* Disable interrupt */ val = p->dma_read(IRQENABLE_L0, lch); val &= ~(1 << lch); p->dma_write(val, IRQENABLE_L0, lch); + /* clear IRQ STATUS */ + p->dma_write(1 << lch, IRQSTATUS_L0, lch); spin_unlock_irqrestore(&dma_chan_lock, flags); } @@ -745,11 +754,8 @@ int omap_request_dma(int dev_id, const char *dev_name, } if (cpu_class_is_omap2()) { - omap2_enable_irq_lch(free_ch); omap_enable_channel_irq(free_ch); - /* Clear the CSR register and IRQ status register */ - p->dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR, free_ch); - p->dma_write(1 << free_ch, IRQSTATUS_L0, 0); + omap2_enable_irq_lch(free_ch); } *dma_ch_out = free_ch; @@ -768,27 +774,19 @@ void omap_free_dma(int lch) return; } - if (cpu_class_is_omap1()) { - /* Disable all DMA interrupts for the channel. */ - p->dma_write(0, CICR, lch); - /* Make sure the DMA transfer is stopped. */ - p->dma_write(0, CCR, lch); - } - - if (cpu_class_is_omap2()) { + /* Disable interrupt for logical channel */ + if (cpu_class_is_omap2()) omap2_disable_irq_lch(lch); - /* Clear the CSR register and IRQ status register */ - p->dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR, lch); - p->dma_write(1 << lch, IRQSTATUS_L0, lch); + /* Disable all DMA interrupts for the channel. */ + omap_disable_channel_irq(lch); - /* Disable all DMA interrupts for the channel. */ - p->dma_write(0, CICR, lch); + /* Make sure the DMA transfer is stopped. */ + p->dma_write(0, CCR, lch); - /* Make sure the DMA transfer is stopped. */ - p->dma_write(0, CCR, lch); + /* Clear registers */ + if (cpu_class_is_omap2()) omap_clear_dma(lch); - } spin_lock_irqsave(&dma_chan_lock, flags); dma_chan[lch].dev_id = -1; @@ -943,8 +941,7 @@ void omap_stop_dma(int lch) u32 l; /* Disable all interrupts on the channel */ - if (cpu_class_is_omap1()) - p->dma_write(0, CICR, lch); + omap_disable_channel_irq(lch); l = p->dma_read(CCR, lch); if (IS_DMA_ERRATA(DMA_ERRATA_i541) &&